Pressurized dough container

ABSTRACT

Without limitation on the scope of the claims, this disclosure embodies a container of spirally wound laminated construction for holding pressurized dough products such as pre-leavened dough and the like wherein the laminations of the container are permanently adhered together in a manner to provide sufficient body wall stiffness to rupture along a pre-determined spiral rupture line upon application of only a moderate indenting force against the body wall, a specific embodiment including a dry bond type adhesive for adhering the layers together and the disclosure also embodying the method of opening a pressurized dough package by applying only moderate indenting force against the side wall of the container to rupture the same without peeling off any portion of the laminations.

ite States Patent [191 Fienup et al.

[541 PRESSURIZED ooucn CONTAINER [75] inventors: Wilbur G. Fienup, St. Louis, Mo.;

James R. Henderson, Louisville, Ky.

[73] Assignee: Boise Cascade Corporation, Boise,

Idaho 2,793,126 5/1957 ,Fienup ..99/172 2,793,127 5/1957 Geist et a1. ..99/172 2,800,267 7/1957 ONeil ....229/5l BP 2,975,068 3/1961 Fienup et al.... ..99/172 3,144,193 Geist et a]. ..229/51 [4 1 Jan. 23, 1973 3/1966 Mack ..229/49 R 3,237,364 3,267,633 8/1966 Goodman ....206/78 B X 3,397,834 8/1968 l-lanlon et a1. ..229/51 8? Primary Examiner-Davis T. Moorhead Attorney-Lawrence E. Laubscher s7 ABSTRACT Without limitation on the scope of the claims, this disclosure embodies a container of spirally wound laminated construction for holding pressurized dough products such as pre-leavened dough and the like wherein the laminations of the container are permanently adhered together in a manner to provide sufficient body wall stiffness to rupture along a pre-determined spiral rupture line upon application of only a moderate indenting force against the body wall, a specific embodiment including a dry bond type adhe sive for adhering the layers together and the disclosure also embodying the method of opening a pressurized dough package by applying only moderate indenting force against the side wall of the container to rupture the same without peeling off any portion of the laminations.

3 Claims, 8 Drawing Figures PMENIEDJAM 23 ms INVENTORS WILBUR G. FIENUP /4 JAMES R. HENDERSON AT TOR NEY '1 PRESSURIZED DOUGH CONTAINER This invention relates to an improved method for opening pressurized dough containers and to a spirally wound container for holding dough products such as p're-leavened dough and the like and which is constructed to permit one-step easy opening without the need of any tools and without any pre we'akening. of the container and is a continuation of application for U. S. Letters Patent Ser. Not 552,804, filed- May 25, 1966.

This invention isan improvement over the invention disclosed and claimed in Us. Pat. No. 2 ,975,068which is assigned to-the assignee hereunder and which embodies the basic concept of a one=step" easy opening spirally'wound container of the type which'r'equires n'o initial pre-weakening step for opening (hereinafter referred to as"nopeel-"" type' containers) and which has a spiral rupturelin'e formed by the butt joint of the intermediate spirally wound body layer and held together only by the inner and outer layers glued to the respective inner and outer surfaces of the body layer.-

fined the pressurizeddoughproduet and'w-as relatively easy to open, some objeotions wer'e-raised to the opening characteristics in thatexcessive in'denting force was required to be applied atthe selected area of the side wall ifstruck-on'a str'a'igh't edge, which has become the customary way. forthe housewife to open pressurizeddoug h packagesrln'order to reducethe forcerequired for opening this first "no p'eel-" container, irnpact against a protruding coriierwa'srequired.

A number ofprior'art ULS patentshave been'issued for packages;forpressurized dough productssuch as such as by removal of at least? a'portio'nof the outer.

wrapper at the time of opening. This permits sufficient strength to be builti into the. container to;- facilitate I manufacture of the contajnerand confine the dough therein during packing, fpio'dfing, shipping, handling and'storage until'it is desiredito' open the package. .Fori convenience this application, containers which require an initial pre-weake'ning step for openingwill' be referred to as peel-mien" containers-in thet'iber can industry the outer layer or wrapper usually con+ stitutes the printed label" and therefore this outer wrapper will be frequently referred toshere'in' as the" "label".

The first no-peel container described above was developed in order to 'elimina-te the'initial pre-weak'ening step required foropening-all peel-open "type-containers. Since the development of'the first no-peel containers, employees of: applicants" assignee have" been constantly working to improve the opening characteristics "of the-fno-peel' type container in' view of the fact that it was -found tdbe somewhat'incohvenient and objectionable to strike-"the container against a protruding corner: This wasalso somewhat objectionable" in that a sharp protruding: corner wouldsometimes penetrate into the dough anirl ca'use a slight permanent deformation: of the' pre-forinedshape of this doughso penetrated.

. bondthe layer's together.. As' would be eitp'ected, these: containers in which heatsealing"polyethylene wasus'ed The principal problem in producing a satisfactory no-peel type container is to provide a container which Will satisfactorily hold the product and yet permit easy opening'by the use of only moderate indenting force such as" is applied by moderate impact against a straight edge thus eliminating the necessity for impact against a protruding corner. It is extremely important to keep in min'd th'at in order for such a no-peel contai'ner to provide a contribution to the art, it must he substantially as easy to open by impact against a straight edge as is the present peel ope'n container on which an initial pre-wealteni'ng step has been performed.

Different types and weights of container materials were tried in attempting to produce a no-peel container-which would have the required opening characteristics and yet would be sufficiently strong to confine the pressurized dough product. However, all of these experiments failed to produce the desired results. The containers which were sufficiently strong to hold the product were difficult to open. All spirally wound ifefri'ge'rated dough containers manufactured by the fiber can industry have been constructed w'itliwater base or aqueous glues which includeanimal, de'xtrine,

rresinbonding'agents. T l lth'as been known by those skilled in theart that ad hesives other than water base glues are. available but none has=been used toany extent in the fiber canindustir'y; Th'euseof heatsealing" polyethylene was tried experimentally by' companies" such as the Aluminuml ompan'y'jof America, ase'viden'ced by it's'booklet entitl'ed 'A'lcoa Dry-Bonding System for Composite Con" tain'e'rs". These adhesives were generally known to t? our invention, for adliesively connecting the layers of spirally wound'pressurized dough containers. In spite of thcfact that it was public knowledge that dry-bond containers were known to be stronger than the containers made withvaqueou's glue, it was decidedto con s ruct andtesfino-peel? type doughcontainer's using a dry-bond adhesive'such as heat sealingpolyethylene to as the bonding agentwere'found to be strong inaxial compression and as strong or stronger in side compression and'in ringtensiIe strength than'those previously made'witnacfueous glue; however, mess containers,

when filled -witli pre-leavened" doughin the usual" manner, opened considerably easier in response to',

containers.

In analyzing the reasons fonthe' imprdvea'e efi ing' properties experienced with the dry-bond construction the renewingfacts-were determined: The paperin'du's try conventionally supplies pape'r board" to its customers inthe fiber canbusine'sswith'a' moisture content of approximately 5 to 8 percent. The water base gl'ue normally addsZ to 3 percent'm'ois'ture to the paper' so that thefiber bodies of the foil lined and foil labeled containers usually contain approximately 7 to 8V2 percent moisture and this percentage will be substantially maintained throughout the shelf life of the packed containers.

The laminated body system of the dry-bond container is relatively free from moisture and is therefore substantially stiffer than the laminated systems which have previously been used. Following this analysis, tests were run on containers constructed in the usual way with water-base glue. These containers were subjected to heat to eliminate the moisture from the system and it was discovered that these containers had approximately the same body wall stiffness and opened substantially as easily as containers manufactured with dry-bond adhesive. This experiment indicates that the moisture content and the stiffness of the body system are important factors in producing the desired opening characteristics of the no-peel" container.

For purposes of this application dry-bond adhesives are defined as being any non-aqueous adhesives which will bond the layers together without softening the body layer when the containers are wound.

It is important in producing a pressurized dough c ntainer which has the desired and predicatable opening characteristics that the container wall be formed fro a single ply of spirally wound body stock having a full length rupture line formed by a pair of adjaclent separate shearing edges of the body stock. These edges are held together by the barrier layers formed by the one-piece inner liner and the one-piece outer label which respectively cover the complete inner and outer surfaces of the body ply and are adhered thereto by means of a dry-bond type of adhesive. The use ofa rybond adhesive along with moisture impervious lner and label layers prevents moisture from the dolugh product and outside humid air from reaching the Body layer surfaces and permits the relatively low mois ure content of the body stock board to be maintained ntil the package is to be opened, at which time said moisture content is critical to the opening cha; acteristics. The stiff shearing edges of the spirally wolund body stock combine with the liner and the label to produce the desired opening characteristics of the container at the rupture line and permit the use of liner and label materials of sufficient strength to hold the pressurized dough product until the container is to be opened.

We have perfected an improved and acceptable onestep method for opening pressurized dough containers and also a new container which permits said method to be successfully carried out.

It is an important object of this invention to provide an improved one-step method for opening a pressurized dough package without any pre-weakening of the package consisting in the application ofa moderate indenting force applied against the container side wall in substantial registration with a rupture line provided therein, the required rupturing force being not substantially greater than the indenting force required to open a pre-weakened peel-open type container.

Another object of this invention is to provide a nopeel spirally wound laminated container for pressurized dough products, which is sufficiently strong to withstand the pressure of the product therewithin but which can be easily opened without any pre-weak'ening whatever, by moderate indenting force against a selected area of the side wall which will cause the container wall to rupture along a pre-determined rupture line and permit easy removal of the pressurized dough.

It is a specific object of this invention to provide a no-peel type laminated dough container which has a spirally wound main body layer with the adjacent separate edges thereof disposed in edge-to-edge abutted relation to provide a rupture line extending the full length of the container, said rupture line being held together by means of inner and outer layers respectively covering the inner and outer surfaces of said main body layer and laminated thereto by means of a drybond adhesive, said body layer having sufficient stiffness to provide shearing edges to produce rupture at said rupture line upon moderate indenting force being applied to the side wall of the container in substantial registration with said rupture line.

Another specific object is to provide an easy opening package including a no-peel type composite container which contains a pressurized dough product and which container is formed from a plurality of spirally wound layers of sheet material including a layer of stiff fibrous intermediate body stock board which provides a spirally extending weakened rupture line which is held together by inner and outer barrier layers covering the respective inner and outer body surfaces and adhered thereto by means of a dry-bond type adhesive which produces and maintains the desired moisture content and stiffness in the fibrous material of the container, both of said barrier layers being ruptured upon application ofa moderate indenting force at said spiral rupture line, such as is produced by moderate impact against a straight edge or by moderate thumb pressure, to release the pressure of said dough product and permit easy removal thereof from the container.

These and other objects and advantages will more fully appear in the following description made in connection with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views, and in which:

FIG. I is an elevational view of a container embodying this invention having parts thereof broken away;

FIG. 2 is a transverse sectional view drawn to a slightly larger scale than FIG. 1;

FIG. 3 is a perspective view showing a package embodying this invention being struck on the straight edge ofa table;

FIG. 4 is a sectional view through the laminated body structure as it appears before impact; and

FIGS. 5a 5d are fragmentary sectional views showing progressively the rupturing action produced by impact of the container wall against a straight edge.

CONSTRUCTION OF CONTAINER In the form of the invention illustrated in the accompanying drawings we provide a composite container C having a laminated spirally wound tubular body wall 10 with a pair of metal ends 11 crimped or seamed thereon. The container in the form shown is filled with a pressurized dough product such as pre-leavened dough D. The container C and the dough D therein combine to form a pressurized dough package which in accordance with conventional marketing practice is maintained under refrigeration until used.

In the dough container C the liner 12 is made from a suitable barrier material which can be easily ruptured and which upon being ruptured will tear from end to end of the container under the pressure of the dough. Aluminum foil laminated to paper has been found to be a suitable liner material. As shown in FIG. 4, the foil is designated 12b and the paper laminated to the foil is designated 12c. The body layer 13 is made from fibrous paper board stock material that is classified as being 'stiff in the paper making industry, such as kraft board.

The label 14 should be a good moisture barrier material which can be easily ruptured and will thentear quickly from end to end of the container under the pressure of the dough. Aluminum foil laminated to kraft paper has been found to be a suitable label material. The foil is designated 14b and the paper is designated 14c, as shown in FIG. 4.

In the form shown the three layers l2, l3 and 14 are all spirally wound. The edges of the body 13 are butted together to form shearing edges which provide a rupture line or butt joint 13a. The adjacent marginal edges ofthe liner 12 are overlapped as 12a and the inner edge is folded under as shown in FlG.'2. The edges of the label 14 are also overlapped as shown at Ma. The rupture line 13a is out of register with the liner and label joints 12a and 14a. The inner and outer layers 12 and 14 bridge the rupture line 13a to reinforce and hold the same together until the container is opened.

We have found that using a dry-bond type adhesive (compared with an aqueous type glue previously used) greatly improves the opening characteristics of the container while at the same time increasing the strength of the body wall. We have also found that the bond obtained between the respective adhered surfaces of the liner and body board and between the label and body board, is more uniform than the bond obtained with the water-base glue and the adhesion is particularly improved along the marginal portions adjacent the butt joint or rupture line 130. We have found that low-density polyethylene is a suitable dry-bond adhesive and has proved to be satisfactory for securely bonding the three layers ofthe container C together. However, any adhesives will work satisfactorily which do not soften the body layer 13 when the containers are wound. In the particular form illustrated both sides of the body board 13 have been coated with polyethylene as identified in FIG.4 by the numerals 13b and 130. At the present' time this appears to be the most efficient method of providing thedry-bond adhesive since both sides can be coated in a single pass operation. It also appears that coating both sides of the board helps to maintain a substantially uniform moisture content in the board which is less affected by moisture after the containers are manufactured and packed with dough. The manufactured tubing is .cut into containers of the desired length and one of the container ends is'closed at the time the containers are manufactured by suitable means such as the metal endclosure 11 secured to the end of the container as by being seamed thereon.

We have found that the most efficient and economical container construction whichhas both the required strength and opening characteristics is aspirally wound laminated container structure in which the rupture line l3a of the body layer .13 is provided by the butt joint formed at the time of winding. This construction also includes complete liner and label layers respectively covering the entire inside and outside surfaces of the body layer, without including any narrow strips or tapes which only partially cover the surface of the layer to which they are applied. It is a possibility that suitable barrier means could be provided for preventing the moisture and oils in the dough from damaging the strength or appearance of the container and, if so, the strengthening function of the liner layer could be eliminated and the reinforcing function could be provided solely by the outer label. It is also a possibility that the outer label layer could be eliminated by providing suitable outer barrier means and the reinforcing function would then be provided solely by the inner liner.

The containers with one end on are normally filled by automatic packing machinery which receives the containers from a conveyor line and inserts the biscuits into the open end of the containers and thereafter the other end is closed as by a metal end 12 seamed thereon.

CRITICAL MANUFACTURING PROBLEMS In the manufacture of spiral composite containers one very important factor which contributes to the strength of the containers is a uniformly tight edge-toedge relation at the butt joint of the body stock board. There are several manufacturing problems in making a tight edge-to-edg'e butt joint; e.g. the accurate slitting of the board stock, positive control of the winding angle, control of the tension on the strip of board being wound, etc. If the butt joint is not maintained in tight dge-to-edge relation during the winding operation this roduces an open butt which materially weakens the an body and makes the same considerably more susceptible to damage during the seaming and packing perations. In order to provide the required opening haracteristics and permit easy opening of the conainer, the strength of the liner l2 and the label 14 hich hold the body layer 13 together is critical and 'must be limited so that it is not too strong or too weak. container with a spiral wound butt joint must rely olelyon the label and liner to resist any resultant compressive as well as twisting forces applied to the container as by seaming and packing machinery. Since the liner and label materials used have very little compressive strength they will yield and wrinkle under compression (with an open butt joint 13a) until the body material shifts sufficiently to bring the spiral edges together and close the butt joint. Such wrinkling and creasing weakens theliner and label material to such an extent that it will frequently fail when ultimately subjected to the tension produced. by the pressure of the dough when the containers are filled. If, however, the butt joint can be maintainedin tight edge-to-edge relation the container will be materially stronger since the abutted edges will support a compressive load without permitting any appreciable shifting of the edges of the board, thus preventing creasing of the liner and label.

THE OPENING OPERATION Containers made in accordance with this invention and packed with a semisolid pressurized product such as pre-leavened dough, can be easily opened by merely striking a pre-determined area of the side wall of the container on the straight edge of a kitchen counter or table as has become customary with present peelopen containers after pre-weakening. This area is in substantial registration with the underlying rupture line 13a and would be indicated on the outside of the label 14. The force of the blow required to open this nopeel" container is not significantly greater than the force required to open the former peel-open containers with the wrapper removed. When the filled container is struck on the table edge at the pre-determined indicated area as indicated above, the side wall is indented at the butt joint. This causes the shearing edges of the relatively stiff body stock to rupture the liner l2 and label 14. The pressure of the dough then causes the container to immediately break open along the full length of the rupture line 13a to quickly release the dough pressure and prevent extrusion and permit easy removal of the dough. The side wall of the container can also be indented by inwardly directed finger or thumb pressure and the container may be opened in this manner if desired. While it is difficult to determine exactly how the indentation operates to produce the initial rupture, it is believed that this local area ofi dentation will produce a spreading apart of the edges f the body stock at the indented portion of the ruptu e line 13a and that this spreading apart of the rupture li e at this point will produce initial breaking of the liner 112 at the area of indentation at the butt joint. This initial breaking of the liner 12 is apparently followed inimediately by rupture of the label 14 in this area. As h s previously been stated, the strength of the contain r will be determined at least in part by the strength oft e liner l2 and the outer label 14 which serve to hold the butt joint together. It will also be apparent that increasing the strength ofthe liner and label will make the container harder to open so that we are confronted wi ih the same problem previously described herei Eliminating moisture in the container through the ue ofa dry-bond type adhesive permits the container to e opened much easier without decreasing the strength f the liner and label material.

We have made a number of comparative tests 0 determine the respective properties of the aqueo s glued container construction compared with the drybond container construction. The aqueous glued containers will be referred to in this application as glued containers. These tests include ease of opening tests which indicate the opening characteristics of the respective containers and also include comparative strength tests, moisture content determination and comparative board stiffness tests. It should be kept in mind in evaluating this test information that the glued" container construction which was used to make the no-peel" containers covered by U.S. Pat. No. 2,975,068 identified on page 1 of this specification proved to be of sufficient strength to stand up satisfactorily in the market so that the strength tests of these no-peel" glued containers have formed a test control or guide for indicating the strength required for the dry-bond containers. As has been stated, however, the glued no-peel type containers required impact on a protruding corner in order to open easily. As stated, this was objectionable. lf not struck on a protruding corner they were too difficult to open to be accepted by the consumer. The control or guide for the ease of opening on a straight edge as distinguished from a protruding corner has been the peel-open container from which the label has been removed. When the label has been removed only the glued-in liner resists the pressure of the dough confined therein. As has been stated, these peel-open containers are exemplified generally by U.S. Pat. Nos. 2,793,126; 2,793,127 and 3,144,193. The constant endeavor in developing the present no-peel container construction has been to make a container with the strength characteristics of the glued" no-peel" container, but having the opening characteristics of the peel-open container with the outer wrapper removed. The dry-bond" container construction is stronger in end-to-end compression than the glued" container construction and is at least as strong in ring tensile strength and in side wall crush strength. We have determined that the moisture content of the entire laminated can system for the glued container construction is between 7 and 8 percent. We have also determined that the moisture content of the dry-bond laminated can system is between 3 and 4 percent and in most instances is approximately 3% percent. All of these tests, of course, were run with identical materials with the exception that the paper board body material used in the dry-bond containers was coated on both sides with the dry-bonding agent prior to winding on the can winder. Our comparative stiffness tests indicate that the dry-bond board containing between 3 and 4 percent moisture is substantially stiffer than a similar board containing between 7 and 8 percent moisture. As previously stated, the paper board body stock has between 5 and 6 percent moisture when it is received from the mills, whether it is coated with dry-bond adhesive or is uncoated.

The opening characteristics of our new dry-bond no-peel container are generally similar to the opening characteristics of the peel-open" type container after the body has been pre-weakened. The opening tests that we have performed indicate that the prior glued no-peel" container requires a great deal more indenting force to produce the rupture of the side wall than is required with the peel-open containers with the outer label removed. These same tests indicate only a slight increase in the force required for opening the new dry-bond no-peel container over the force required to open the peel-open" type container which has had the outer label removed.

It will be seen that we have provided an improved one-step method for opening pressurized dough containers which consists in applying a moderate indenting force against a selected area of the side wall of the dough filled package, as by moderate impact against a straight edge ofa table or kitchen counter or by thumb pressure against said side wall to cause rupture of the container side wall along a pre-determined spiral rupture line extending the full length of the container to permit easy removal of the dough from the container. We have also provided a novel pressurized dough container specifically constructed to permit easy opening thereof without any pre-weakening of the container wall.

What is claimed is:

1. An easy one-step opening no-peel" type spirally wound container particularly designed for packaging pressurized dough products, said container comprising:

A. a spirally would laminated body wall construction including an intermediate stiff body layer made from fibrous board material with the moisture content thereof being between 3 and 4 percent to 3. An easy one-step opening no-peel type spirally wound container particularly designed for packaging pressurized dough products, said container comprising:

A. a spirally wound laminated body wall construction produce the required stiffness in said body layer, 5 including a Stiff y l yer ad fr m fibrous 1. id b d layer h i a i f Separate dboard material with the moisture content thereof jacent edges butted together to form shearing being between 4 Percent to Produce the edges which define a spirally disposed rupture required st'ffn4e55 l body x line extending the full length of the container, F b layer havmg a of Separate 3 3 inner and-outer barrieflayers, v acent edges butted together to form shearing 1. respectively covering the entire inner and outer i l ply'ovlde splrally dlsposed fupture surfaces of said body and bridging said rupture hrle extefldmg t fun lerfgth of the line and B. moisture-impervious barrier means covering the 2. permanently laminated to said body surfaces, einme and uter surfaces of said body layer 3. said barrier layers being of a moisture-impervisubs,tantlally solate Sald body a r from Gus material tact with the product confined wlthm the conto combine with the body layer to hold the tamer and from the moisture of the ambient a1r to dough product until the container is opened. prgvem absorption by Sald.body layer and mamb. to provide barrier properties to substantially Sufficleilt" body wall. Stiffness to .prpduce the desired predictable opening characteristics, 'solate Sald body lay?! f contaq wnh the I C. at least one reinforcing layer permanently product confilfed wthm the f i and laminated to said body layer between said body from the mo'stflre of h amb'em to layer and at least one of said barrier means, said a a t' by Sam body layer and reinforcing layer bridging said rupture line and maintain sufficient body wall stiffness to 2 being Ofadry bond adhesive material Produce the dslred Predictable opening 1. to combine with said body layer to hold the characteristics which permit rupture at said dough product um the container is Opened, rupture line by striking with moderate indentnd force a predetermined area of Said y 2. to rupture along said rupture line upon impact wall against the straight edge of a kitchen produced by striking with amoderate indenting counter or the like, force a Rredetermined area of said body wall C. and means for closing the ends ofthe container. agaItISt t e Straight edge of a kltchen counter or 2. The container set forth in claim 1 and said barrier the layers being laminated to the respective surfaces of said and means for closmg the ends of the Contamerbody layer by means ofa dry-bond type adhesive; 

1. An easy one-step opening ''''no-peel'''' type spirally wound container particularly designed for packaging pressurized dough products, said container comprising: A. a spirally wound laminated body wall construction including an intermediate stiff body layer made from fibrous board material with the moisture content thereof being between 3 and 4 percent to produce the required stiffness in said body layer,
 1. said body layer having a pair of separate adjacent edges butted together to form shearing edges which define a spirally disposed rupture line extending the full length of the container, B. inner and outer barrier layers,
 1. respectively covering the entire inner and outer surfaces of said body and bridging said rupture line and
 2. permanently laminated to said body surfaces,
 3. said barrier layers being of a moisture-impervious material a. to combine with the body layer to hold the dough product until the container is opened. b. to provide barrier properties to substantially isolate said body layer from contact with the product confined within the container and from the moisture of the ambient air to prevent absorption by said body layer and maintain sufficient body wall stiffness to produce the desired predictable opening characteristics which permit rupture at said rupture line by striking with moderate indenting force a predetermined area of said body wall against the straight edge of a kitchen counter or the like, C. and means for closing the ends of the container.
 2. permanently laminated to said body surfaces,
 2. The container set forth in claim 1 and said barrier layers being laminated to the respective surfaces of said body layer by means of a dry-bond type adhesive.
 2. to rupture along said rupture line upon impact produced by striking with a moderate indenting force a predetermined area of said body wall against the straight edge of a kitchen counter or the like, D. and means for closing the ends of the container.
 3. An easy one-step opening ''''no-peel'''' type spirally wound container particularly designed for packaging pressurized dough products, said container comprising: A. a spirally wound laminated body wall construction including a stiff body layer made from fibrous board material with the moisture content thereof being between 3 and 4 percent to produce the required stiffness in said body layer,
 3. said barrier layers being of a moisture-impervious material a. to combine with the body layer to hold the dough product until the container is opened. b. to provide barrier properties to substantially isolate said body layer from contact with the product confined within the container and from the moisture of the ambient air to prevent absorption by said body layer and maintain sufficient body wall stiffness to produce the desired predictable opening characteristics which permit rupture at said rupture line by striking with moderate indenting force a predetermined area of said body wall against the straight edge of a kitchen counter or the like, C. and means for closing the ends of the container. 